Motorcycle helmet



FIG. 1 is a rear view of a motorcycle helmet showing my new design;

FIG. 2 is a bottom view thereof, the details shown in broken lines form no part of the claimed design;

FIG. 3 is a front and left side perspective view thereof;

FIG. 4 is a front view thereof;

FIG. 5 is a rear and left side perspective view thereof;

FIG. 6 is a left side view thereof;

FIG. 7 is another rear and left side perspective view thereof;

FIG. 8 is a top view thereof; and,

FIG. 9 is a right side view thereof. 

The ornamental design for a motorcycle helmet, as shown and described. 